The present invention is related to storage media. More particularly, the present invention is related to systems and methods for synchronizing to information maintained on a storage medium.
A typical digital magnetic storage medium includes a number of storage locations where digital data may be stored. Data is written to the medium by positioning a read/write head assembly over the medium at a selected location, and subsequently passing a modulated electric current through the head assembly such that a corresponding magnetic flux pattern is induced in the storage medium. To retrieve the stored data, the head assembly is positioned anew over the track. In this position, the previously stored magnetic flux pattern induces a current in the head assembly that can be converted to the previously recorded digital data.
The storage locations on the magnetic storage medium are typically arranged as a serial pattern along concentric circles known as tracks. FIG. 1 shows a storage medium 100 with two exemplary tracks 150, 155 as dashed lines. The tracks are segregated by servo data written within wedges 160, 165. These wedges include data and supporting bit patterns that are used for control and synchronization of the head assembly over a desired storage location on storage medium 100. The data and supporting bit patterns used to derive the control and synchronization is depicted as a pattern 110 that includes a preamble 152, a sync 154, a gray code 156 and a burst 158. It should be noted that while two tracks and two wedges are shown, hundreds of each would typically be included on a given storage medium. Further, it should be noted that a sector may have two or more bursts.
Burst 158 includes one or more sinusoidal signals that can be used to determine radial position of the head assembly relative to the track. In a traditional scenario, burst 158 is detected within a given sector and used to determine radial position of the head assembly relative to the track. Once radial position is determined, the head assembly is immediately moved to compensate for any positioning error. In various cases, however, noise or other factors affect the information obtained from burst 158. At times, this can result in inaccuracies in positioning the head assembly.
Hence, for at least the aforementioned reasons, there exists a need in the art for advanced systems and methods for increasing the accuracy of head assembly positioning.